Multiple-copy electrostatic machine control

ABSTRACT

An electrostatic copier to feed sheet by sheet piled electrophotographic paper and transfer the image of the original sheet onto the paper, including a microswitch disposed at the entrance of an exposure station which is actuated and switches circuits for a charging device and a lamp when the electrophotographic paper charged on the switching on of a copying start switch enters the exposure station. A second microswitch disposed at the exit of the exposure station stops supplying electricity to the charging device, the lamp and two preset switches for copying a plurality of sheets when the tail end of the electrophotographic paper leaves an actuating member.

0 United States Patent in] 3,604,79

[72] Inventor Masaya Ogawa [56] References Cited '9" UNITED STATESPATENTS g 2315 3,330,179 7/1967 Ferfahs m1. 355/14 Paemed Sept-14,19."3,416,860 12/1968 Miho evich etal. 355/14 X 73] Assignee MinoltracarneraKabushiki Kaisha Primary Examiner-Samuel S. Matthews Osaka, JapanAssistant Examiner--M. L. Gellner [32] Priority Jan. 31, 1968Attorney-Mason, Fenwick and Lawrence [33] Japan [31] 43-6461 [54]MULTIPLE-COPY ELECTROSTATIC MACHINE ABSTRACT: An electrostatic copier tofeed sheet by sheet piled electrophotographic paper and transfer theimage of the original sheet onto the paper, including a microswitchdisposed at the entrance of an exposure station which is actuated andswitches circuits for a charging device and a lamp when theelectrophotographic paper charged on the switching on of a copying startswitch enters the exposure station. A second microswitch disposed at theexit of the exposure station stops supplying electricity to the chargingdevice, the lamp and two preset switches for copying a plurality ofsheets when the tail end of the electrophotographic paper leaves anactuating member.

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A *rrOR/ E 8 MULTIPLE-COPY ELECTROSTATIC MACHINE CONTROL The presentinvention'relates to an improvement in an elec-.

When a pile ofelectrophotographic paper is placed through the inlet 8 ona paper table 12 within the main frame 2, a

microswitch MS-7 inserted in the circuit of a pilot lamp PL-E trostaticcopier and more particularly to an electrostaticcopier for automaticallymaking a number of copies from one' original sheet.

Conventionally, in case a number of copies were to be made by anelectrostatic copier from the same original sheet, inconveniencesencountered were that the start switch had to be depressed every time acopy was made and that the number of the copies had to be counted. Anobject of the present invention is to provide an apparatus forfull-automatically making a desired number of copies with highefficiency.

In accordance with the present invention, two preset switches areprovided in an electrical circuit for controlling the operations offeeding electrophotographic paper and of copying the original sheet, thecontacting member of each of the preset switches being adapted to be setto a desired contact among a plurality of the contacts of the switch. Onthe other hand, a preset switch is associated with the electrical circuits of a feed motor for driving a feed roller upon being actuated by astart switch and of a relay which closes the self-maintaining contactupon being actuated by a start switch, the preset switch being disposedso as to be in parallel with the start switch. in the circuit of theother preset switch, there is provided a presetting solenoid, and adrive means such as a ratchet mechanism to be driven by the solenoid isassociated with the preset dial shaft so that the contacting members ofthe respective preset switches may be rotated into contact with thecontacts of the switches.

The Circuit of the start switch and the circuits of the respectivepreset switches are connected to the main switch in the circuit of thecopier through the Contact of a microswitch which is adapted to openthis contact and close the other contact when the electrophotographicpaper reaches the entrance of an exposure station and which is adaptedto close the former Contact and open the latter contact when the paperleaves the actuating member of the contacts. In the respective circuitsof the preset switches are provided two contacts to be opened and closedby means of a relay, and the current is supplied to the relay to closethe contacts through the latter contact of the above-mentionedmicroswitch and another microswitch which is disposed in parallel withthe contact of the microswitch and which is adapted to open a contactwhen the tail end of the electrophotographic paper has passed theexposure station and to keep the Contact closed while theelectrophotographic paper is passing through the exposure station.

With the structure described above, the object of the present inventioncan be accomplished. The practical features of the present inventionwill become apparent from the following description of the embodimentand accompanying drawings, in which:

FlG. l is a perspective view of an electrostatic copier embodying thepresent invention;

FIG. 2 is a front view in vertical section;

FIG. 3 is a schematic perspective view showing the clutch mechanism;

F IG. 4 is a schematic perspective view showing a mechanism for drivinga preset dial; and

FIG. 5 is a connection diagram of the electrical control circuit.

Referring to the drawings, the numeral 1 designates a document stationto be guided on a main frame 2 along a guide rail 3 and adapted for areciprocating movement toward the right and left. As already known, thedocument station 1 includes a glass plate 4 for inspecting the originalsheet and a document cover 5. The front face of the main frame 2 isprovided with a main switch SM, start switch SS, exposure-adjusting dial6, preset dial 7, etc. The right side surface is formed with an inlet 8for feeding electrophotographic paper and the left side surface isprovided with an outlet 9 for discharging processed copies and a copyreceiver 10.

shown in FIG. 3 is opened. On the top surface of the pile ofelectrophotographic paper 11 at the left end is disposed a feed roller13 to be driven by a feed motor MF.

When the main switch SM is turned on (see FIGS. 2 and 5), a pilot lampPL is lighted, and a main motor MM is actuated to drive a chainmechanism 14, which further drives paper-driving rollers 15, 16, 17, 18,19 and 20 and squeeze rollers 22 which are always kept clean by means ofa cleaner 21. Furthermore, a fan motor MB is rotated to drive a fan (notshown) and send a blast through a duct 23 into a heat-fusing portion 24.A pump motor MP is also rotated to drive a pump 25 and supply thedeveloper within a tank 26 into a developing device 28 through a conduit27 and further back into the tank 26. A heater H whose circuit is openedor closed by a thermostat TS is charged to heat the blast supplied tothe heat-fusing portion 24 through a duct 23. When the temperature ofthe heated blast exceeds a certain level, the thermostat is actuated toopen the circuit of the heater H, while in case the temperature lowersbelow a certain level, the circuit is closed.

At the entrance of a path 31 provided in the exposure station A, thereis disposed a microswitch MS-2 which is so adapted that, when noelectrophotographic paper 11 is in transit, it keeps the Contact 2aclosed which is connected to the start switch SS while leaving the otherContact 2b open and when the electrophotographic paper 11 passes, itopens the contact'2a and closes the contact 2b.

When the start switch SS is turned on, the circuit of the feed motor MPis closed to drive the feed roller 13, whereupon an uppermost sheet inthe pile of electrophotographic paper 11 is fed onto the driving rollers15 driven by the main motor MM and at the same time a relay RY-l whichis connected in parallel with the feed motor MP is energized to closethe contacts a and b and generate a high voltage in a charging device HVthrough the contact a. Through the contact b and microswitch MS-2, thecircuits involving the feed motor MF and relay RY-l are closed, and evenwhen the start switch SS is turned off, the current continuously flowsthrough the feed motor MF, relay RY-l and charging device HV. Theelectrophotographic paper 11 fed onto the driving rollers 15 is drivenby the rollers 15 and delivered from a guide 29 to the charging deviceHV where it is sensitized. Further driven along the driving rollers 16,guide 30 and driving rollers 17, the sheet reaches the entrance of thepath 31 in the exposure station A.

At the entrance of the path 31 of the exposure station A, there isprovided the microswitch MS-2 as aforementioned. When theelectrophotographic paper 11 approaching the path 31 comes into Contactwith the contacting member of the microswitch MS-2, the switch MS-2opens its contact 20 and closes the Contact 2b, thus serving as achangeover switch.

When the Contact 2a of the microswitch MS-2 is opened, the circuitsincluding the relay RY-l and feed motor MF are opened therebydeenergizing the feed motor MF, and the feed roller 13 is thereforehalted on the next sheet of the electrophotographic paper 11. Since therelay also gets deenergized, the contacts a and b are opened. Althoughthe supply of current to the charging device HV is consequentlyinterrupted for a moment, the microswitch MS-2 which closes contact 2bpermits the relay RY-2 to be energized to close the contacts 0 and d, sothat the current supply to the charging device l-lV- is resumed throughthe contact c to get the electrophotographic paper 11 sensitized. Thelamp L is also turned on through the contact d.

When the contact 2b of the microswitch MS-2 is closed, a stopper releasesolenoid SOL-3 and relay RY-3 are energized. The stopper releasesolenoid SOL-3 turns the stopper 32 positioned at the left end of thedocument station 1 clockwise in FIG. 2 to thereby enable the documentstation 1 to move leftward while associating the tail end of the stopper32 with a microswitch MS-S to get its contact closed.

Upon being energized as above described, the relay RY-3 opens thecontact e and closes the contact f. Thus, when the contact f is closedand the contact of the microswitch MS-S is closed, an actuating solenoidSOL-1 is brought into energization through a microswitch MS-6. (Thismicroswitch is a safety switch which is adapted to be opened only whenthe document station I overruns leftward in FIG. 2 and which otherwisekeeps the contact always closed.) The actuating solenoid SOL-l, whenenergized (see FIG. 3), brings a group of feed gears 33 meshing with agear at one end of the driving roller 15 into meshing engagement with aclutch gear 34 and rotates the clutch gear 34 in the direction of anarrow M to thereby drive the document station I leftward in FIG. 2 bymeans of a chain sprocket 35 and chain 36 for driving the documentstation. Furthermore, simultaneously with the meshing engagement of theabove-mentioned feed gear group 33, the contact of a microswitch MS-4inserted in the circuit of the return solenoid SOL-2 to be describedlater is opened.

The lamp 1.. has already been turned on upon this operation of theaforementioned relay RY-2 and as shown in FIG. 2 the lamp illuminatesthe original sheet from under the document station 1 by means of lightreflectors 37 and 38, the light being adapted to strike the exposurestation A by means of reflecting mirrors 40 and 41, a mirror lens 42 andexposure control plate 43 which are disposed in a dark box 39 of theoptical system to form the image of the original sheet on theelectrophotographic paper 11 passing through the path 31 in the exposurestation A and effect exposure.

The undersurface of the document station 1 is provided with an actuatingmember 44 for the contacting member of a microswitch MS-l. While theactuating member 44 is in contact with the microswitch MS-l, namely onlywhile the document station 1 stays at the right end in FIG. 2, thecontact of the microswitch MS-l is kept open, and upon the documentstation 1 being initiated into leftward travel, the contact is closed,while when the document station is completely returned, the contact isbrought into an open position again. The gear ratio of the group of feedgears 33 is so determined that the speed of feeding theelectrophotographic paper 11 may be synchronized with that of theleftward travel of the document station 1.

At the terminal end of the path 31 in the exposure station A there isdisposed another microswitch MS-3 which is so adapted that, when theforward end of the electrophotographic paper 11 which has been exposedto the light as aforementioned is brought into contact with thecontacting member of the microswitch MS-3, the contact of the switch maybe thereby closed. As shown in FIG. 5, the microswitch MS-3 is arrangedin parallel with the microswitch MS-2. By the contact being closed,current is supplied to the relays RY-2, RY-3, and stopper releasesolenoid SOL-3 to actuate respective mechanisms described above.

When the electrophotographic paper 11 has been exposed and the rear endthereof has left the contacting member of the microswitch MS-3 afterpassing through the exposure station A, the contact of the microswitchMS-3 is opened to terminate the supply of current to the relays RY-2,RY-3 and stopper release solenoid SOL-3. Accordingly, the relay RY2opens its contacts and d to stop e supply of current to the chargingdevice HV and turn off the lamp L. The relay RY-3 gets deenergized toopen the contact f and close the contact e and the current supply to theactuating solenoid SOL-l is thereby terminated, while the stopperrelease solenoid opens the contact of the microswitch MS- by means ofthe stopper. 32.

The actuating solenoid SOL-l, upon being deenergized (see FIGS. 3 and5), moves the feed gear group 33 out of the meshing engagement with theclutch gear 34 to thereby halt the leftward travel of the documentstation 1 and closes the contact of the microswitch MS-4. Since thecontact of the microswitch MS-l has been closed by the leftward travelof the document station 1 as aforementioned, the return solenoid SOL-2is energized by the contact e of the relay RY-3 which is brought intoclosed position. By bringing a group of return gears 45 meshing with agear on one end of a driving roller 17 which is driven by the main motorMM into meshing engagement with a clutch gear 34, the clutch gear isrotated in the direction of an arrow N to drive the document station Irightward in FIG. 2 by'means of a clutch sprocket 35 and chain 36 fordriving the document station. Since there is no need to synchronize thereturning movement of the document station 1 with the speed of feedingthe electrophotographic paper 11, the gear ratio of the return gears 45is suitably determined to effect rapid returning movement. When thedocument station 1 has been returned to the right end in FIG. 2, theactuating member under the document station 1 comes into contact withthe contacting member of the microswitch MS-l to open the contact of themicroswitch MS-l, so that the circuit of the return solenoid SOL-2 isopened and the solenoid is deenergized. The return gear group 45 isconsequently moved out of meshing engagement with the clutch gear 34,whereby the document station 1 is brought to a halt. Although the leftend of the document station 1, during the returning movement of thestation, contacts the stopper 32, trouble-free return is ensured since aspring 46 is acting on the stopper 32 as illustrated.

While the operations described are carried out, the electrophotographicpaper, passing along the driving rollers 18, guide 47, driving rollers19 and a guide 48 in the developing device, is brought into contact withthe developer, which turns the sensitized image aforementioned into avisible image. With developer squeezed by squeeze rollers 22, it is sentinto the heat-fusing portion 24 to be heat-fused with a blast which issupplied through the duct 23 and heated by the heater H. Guided by aguide 49 and driven by driving rollers 20, the sheet is delivered ontothe copy receiver 10 through the discharge outlet 9.

It will be apparent from the above description that with the foregoingstructure alone, every time the start switch SS is depressed, theelectrostatic copier operates to make one copy. Accordingly, in case anumber of copies are to be made from an original sheet, the start switchSS must be pushed down every time the document station I is completelyreturned.

In accordance with the present invention as shown in FIGS. 4 and 5,there are provided, in the electrical control circuit of theelectrostatic copier, two switches PRa and PRb of rotary type whichperform switching action at the contacts of a preset dial 7, each of theswitches PM and PRb being provided with a suitable number, correspondingto the number of the copies, of contacts, M 1,2,...Jlin circulararrangement. The contactsM, 2,3,"!!! of the switch PRa are connected inseries into one circuit, with the contact l left independent of theabove circuit. As to the other switch PRb, the contacts 2, 3 areconnected in series into one circuit and the contactsM and l arerespectively left alone independently. The switch PRa' is connected tothe circuit of the start switch SS so as to be parallel therewith andthe switch PRb is connected to the circuit including the start switchSS, feed motor MF, and relay RY-l and to the circuit including theswitch PRb, the feed motor MF and switch PRa respectively in parallelconnection. In the circuit involving the switch PRb is inserted inseries a presetting solenoid SOL-4 whereby a preset dial shaft 50 isdriven by means of a ratchet mechanism for switching the preset contactsto be later described so that the contacts of the above-mentioned PRaand PRb may be switched every time a sheet of the electrophotographicpaper II is subjected to coping operation. Furthermore, contacts 8 and hwhich are adapted to switch the circuits of PRa and PRb are provided inthese circuits respectively in series in operative relationship with therelay Ry-2 which effects switching action to the contacts c and dadapted to open and close the circuits of the charging device and d lampL respectively.

Each of the preset switches and the mechanism for operating the same areshown in FIG. 4. Around the insulating discs 51a and 51b fixedly mountedon the preset dial shaft 50 are provided electroconductive plates 52aand 52b of doughnut shape, contacting members 530 and 53b projectingfrom a portion thereof serving as changeover switches. Around theelectroconductive plates 52a and 52b are respectively disposed contactsh i l 2 1, Q in radial arrangement, the insulating plates being providedwith connecting members 550 and 55b which are always kept in contactwith the electroconductive plates 52a and 52b. Numeral 56 designatessupport members for fixedly supporting the insulating plates 54. Thepresetting solenoid SOL-4 drives a ratchet pawl 58 supported on a shaft57 and moves a ratchet wheel 59 on the shaft 50 by one pitch at a time.

In accordance with the above structure, in case six copies are to bemade from the same original sheet, the original sheet is first set onthe document station 1 and the scale of the preset dial 7 is set at 1thereby bringing connecting members 55a and 55b into contact with thecontacts 6 of the switches PRa and PRb.

When the main switch SM and start switch SS are turned on, theelectrostatic copier is initiated into copying operation to carry outthe same operation as the. foregoing until the electrophotographic paper11 closes the contact of the microswitch MS-S. When the rear end of theelectrophotographic paper 11 leaves the contacting member of themicroswitch MS-Z to open the contact 2b of the microswitch MS-2 andclose the contact 2a, the relays RY-Z, RY-3, stopper release solenoidSOL-3 are being supplied with current through the microswitch MS-3. Whenthe contact 2a of the microswitch MS-3 is closed, the relay RY-2 closesthe contacts 3 and h in operative relationship with the contacts and d,so that through the contact i of the preset switch PRa, the relay RY-land feed motor MF are supplied with current, the contacts a and b of therelay RY-l are closed and the feed motor MP is initiated into operation.Thus, a sheet of electrophotographic paper 11 is initiated into feedingoperation by the feed roller 13 with a predetermined space apart from apreceding sheet 11 which is being driven through the exposure station A.

On the other hand, the relay RY-Z, closing the contact h energizes thepresetting solenoid SOL-4, through the contact h and preset switch PRband turns the ratchet mechanism illustrated in FIG. 4 by one tooth,thereby releasing the contacting members 53a and 53b of respectivepreset switches PRa and PRb from the contacts 1 onto the contacts 5 Whenthe rear end of the electrophotographic paper 11 passing through theexposure station A leaves the contact of the microswitch MS-3, thecontact of the microswitch MS-3 is opened to deenergize the relays RY-2,RY-3 and stopper release solenoid SOL-3, so that the contacts 0, d, andf of the relays RY-2 and RY-3 are opened and the contact e is closed,the return solenoid SOL-2 further being initiated into operation toreturn the document station 1 as already described. The lamp L is alsoturned off. Simultaneously with the opening of the contacts 0 and d ofthe relay RY-Z, the contacts g and h are opened, and the presettingsolenoid SOL-4 is deenergized, while through the preset switch PRa thecircuit including the feed motor MF and relay RY-l is opened. However,since the relay RY-l keeps the contacts a and b closed and the circuitincluding the contact 24 of the microswitch MS-Z and the contact b ofthe relay RY-l is closed, the relay RY-l keeps the contacts a and bclosed in self-maintaining state even when the contact g of the relayRY-2 is opened. The feed motor MP is therefore supplied with currentcontinuously and the charging device HV is also charged through thecontact a.

Following the first sheet of electrophotographic paper 11 which haspassed through the exposure station A, the second sheet ofelectrophotographic paper is fed by means of the feed roller 13. Themicroswitch MS-3, when opened, effects rapid returning movement of thedocument station 1 while the above-mentioned operation is being carriedout, and the contact of the microswitch MS-l, when brought into openposition, halts the document station 1. When the forward end of thesecond sheet of electrophotographic paper 11 reaches the exposurestation A and the microswitch ,MS-Z closes the contact 2b while openingthe contact 2a, the current supply to the feed motor MF and relay RY-lis terminated as already mentioned, while on the other hand the documentstation I is initiated into leftward travel to repeat the foregoingoperation. In this manner, each contacting member of the microswitchesPM and PRb is moved into contact with the contacts 5 1, Q, and 2 insuccession to produce the third, fourth, fifth copies. When thecontacting members 53a and 53b come into contact with the contacts 1,the sixth sheet of the electrophotographic paper 11 is sent out, sincethe contacts l are independent of the circuits connecting the contacts1, 12 and are not connected to the contacts 3 and h of the relay RY-2.The forward end of the electrophotographic paper 11, upon reaching theexposure station A, closes the contact 2b of the microswitch MS-Z whileopening the contact 2a, with the result that the current supply to thefeed motor MF and relay RY-l is halted. The forward end of the sheet 11further closes the contact of the microswitch MS-3 and the tail end ofthe sheet 11, thereafter leaving the contacting member of themicroswitch MS-Z, further closes the contact 2a of the microswitch MS-2and opens the contact 2b. Even when the contacts g and h of the relayRY-Zare closed, the preset switches PRa and PRb are open because thecontacts l are independent. Accordingly, the current is not supplied tothe .feed motor MF and relay RY-l, nor to the presetting solenoid SOL-4.Therefore, the feed roller 13 is not rotated, nor are the contactingmember of the preset switches PRa and PRb rotated by the ratchetmechanism. That is to say, after the sixth (last) sheet of theelectrophotographic paper 11 has been sent out, the feed motor MF is nolonger driven with the contacts a and B of the relay Ry-station I keptopen. As a result, when the document stationl is completely returned andthe sixth sheet 11, after being subjected to development and heatfusing, is delivered onto the copy receiver 10, further operation is nolonger carried out but respective motors and the like are all brought toa halt by opening the main switch SM.

it will be apparent from the above description that when only one copyis to be made from an original sheet, the main switch SM and startswitch SS are turned on with the respective contacting members of thepreset switch PRa and PRb brought into contact with the contacts Lbymanipulating the preset dial 7.

Next, in case an indefinite number of copies are to be made, the presetdial 7 is manipulated to bring the contacting members of the presetswitches PRa and PRb into contact with the contacts M, and then the mainswitch SM and start switch SS are turned on. Since the contact M of thepreset switch PRb, just as the contactl, is independent of the othercontacts 2, 1 0 the circuit of the presetting solenoid SOL-4 is formedinto a closed circuit independently of the action of the other operatingmembers by means of the preset switch PRb, so that the ratchet mechanismis entirely left out of operation. On the other hand, the contact M ofthe preset switch PM is connected in series to the contacts g 1g, andaccordingly when the contact g is closed by the relay RY-Z, the circuitparallel with the start switch SS, namely the circuit of the presetswitch PRa is closed. At this time, in case the contact 2a of themicroswitch M54 is closed and the contact 3 of the relay RY-Z is alsoclosed, the contacts a and b are closed so as to supply current to thefeed motor MF and to render the relay RY-l self-maintaining.

That is to say, the preset switch PRa, when closed, permits the relayRY-l to repeat the self-maintaining action every time theelectrophotographic paper passes through the exposure station, and thefeed roller 13 thereby sends out the electrophotographic paper one sheetafter another with a suitable space between sheets, while thereciprocating movement of the document station 1 and repeated movementsof other operating members are performed. On the other hand, since thepresetting solenoid SOL-is left out of operation, the contacting membersof the preset switches PRa and PRb are not rotated but remain in contactwith the contacts 1!. That is, the copying operation can be indefinitelyrepeated.

Indicated as at MS-lb in the drawing is a microswitch adapted forswitching action integrally with the microswitch MS-l. The microswitchMS-lb is inserted in the circuit of the heater H in parallel with thethermostat TS to prevent overheating of the device and improperheat-fusing operation and effect heat fusing within an extremely shortperiod of time.

While the foregoing description has been made in respect to anembodiment of a copying machine of the type having a movable documentstation, the present invention can also be embodied in an electrostaticcopier of a type in which exposure is effected by a moving illuminationand lens.

What is claimed'is:

I. An electrostatic copier with electric circuits comprising a feedmotor to drive a paper feed roller by being actuated with a startswitch; a relay to close a self-maintaining contact by being actuatedwith the start switch; a first preset switch having a plurality ofcontacts connected in parallel with the circuit of the start switch; asecond preset switch having a plurality of contacts connected inparallel with the circuit of the relay; a presetting solenoid to switchthe contacts of the preset switches every time a sheet ofelectrophotographic copy is made; a first pair of switches disposed inthe circuits of the preset switches; a second pair of switches disposedin the circuits of a charging device and a lamp; and a relay to actuatethe first and second pair of switches.

2. An electrostatic copier as claimed in claim I in which the circuitsof the start switch and the preset switches are connected with thecircuit of a main switch through a first contact of a microswitch toopen the first contact and close a second contact when theelectrophotographic paper reaches an exposure station and to open thesecond contact and close the first contact when the electrophotographicpaper leaves the actuating member of the first and second contacts.

3. An electrostatic copier as claimed in claim 2 in which a secondmicroswitch is connected in parallel with the second contact of thefirst-mentioned microswitch to close a contact and supply electricity tothe relay and close the first pair of switches when the tail end of theelectrophotographic paper has passed the exposure station.

1. An electrostatic copier with electric circuits comprising a feedmotor to drive a paper feed roller by being actuated with a startswitch; a relay to close a self-maintaining contact by being actuatedwith the start switch; a first preset switch having a plurality ofcontacts connected in parallel with the circuit of the start switch; asecond preset switch having a plurality of contacts connected inparallel with the circuit of the relay; a presetting solenoid to switchthe contacts of the preset switches every time a sheet ofelectrophotographic copy is made; a first pair of switches disposed inthe circuits of the preset switches; a second pair of switches disposedin the circuits of a charging device and a lamp; and a relay to actuatethe first and second pair of switches.
 2. An electrostatic copier asclaimed in claim 1 in which the circuits of the start switch and thepreset switches are connected with the circuit of a main switch througha first contact of a microswitch to open the first contact and close asecond contact when the electrophotographic paper reaches an exposurestation and to open the second contact and close the first contact whenthe electrophotographic paper leaves the actuating member of the firstand second contacts.
 3. An electrostatic copier as claimed in claim 2 inwhich a second microswitch is connected in parallel with the secondcontact of the first-mentioned microswitch to close a contact and supplyelectricity to the relay and close the first pair of switches when thetail end of the electrophotographic paper has passed the exposurestation.